


You can just stay here right...in my world?

by Lightrina



Category: Underfell AU - Fandom, Undertale (Video Game), Undertale AU - Fandom, underswap
Genre: Alternate Universe - Underfell, Alternate Universe - Underswap, F/M, Underswap Papyrus, Undertale AU, Yandere, Yandere Papyrus
Language: English
Status: In-Progress
Published: 2017-04-04
Updated: 2017-12-13
Packaged: 2018-10-14 18:13:12
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence, Rape/Non-Con
Chapters: 4
Words: 9,144
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10541844
Author URL: https://archiveofourown.org/users/Lightrina/pseuds/Lightrina
Summary: Frisk is already living a happy pacifist life in the Underfell world, with her Sans. He even gave her a nice collar with a red gem in the center to mark her as his mate. A truly happy world for the newly wed couple, but some otherworldly viruses come to their world and tears it apart ripping parts in the timeline connecting worlds. Sans tries hard to protect her but she falls into Underswap's  timeline. What at first seems like a kinder world then the one she came from turns dark when she turns down underswap Papyrus's love.  And he teaches her the real meaning of L.O.V.E , but her new friends don't believe her that Papyrus would ever do any of that.





	1. prologue

The alarm was buzzing loudly in Frisk's new apartment, She slowly shifted in bed not quite wanting to get up yet. The alarm was still going on, there was a low grumble coming from her skeleyhubby his eye sockets dark as he glared at the clock then he smashed the clock.

"Sweetheart...." Sans said. The human stayed quiet pulling the blanket over her head.

"Hey...babe you forgot to turn off the alarm." Sans said waiting for Frisk to say anything but she just grumbled and shifted to her other side, he tried poking her " Hey, hey." Frisk still would not get up. Sans sighed.

"Fine...you asked for it." Sans said as he began to tickle her awake.

"Sans hehehe......stop.....hehehe.. I am up...I'm up." Frisk tried to talk as she was getting tickled.

"Nope, sorry babe but this is too fun." Sans said with his toothy grin.

The young couple stayed in bed tickling each other, and enjoying a lover's embrace.

"Why did you forget to turn off the alarm sweetheart, you normally don't forget stuff like that?" Sans asked.

"I was just so...tried after last night..." Frisk blushed under Sans her eyes not meeting his.

"Oh I guess you could say I made you BONE tried." Sans said with a wider grin just as he was about to kiss his shy lover. A loud slam came from the door.

"SANS NO SANS JUST NO. ITS TOO EARLY FOR THIS AHHHHHHH!!!!" Papyrus yelled as he pulled Sans off the bed, lucky everyone was still dressed.

"Boss really come on." Sans said as he rubbed his skull.

"No Sans you come on. You told me we were all going to go to the lake today." Papyrus said.

Then a little yellow flower peeked from the hall way. "Frisk you said we would try the treat you were telling me about."

Even though they were married Sans and Frisk lived with Papyrus and Flowey. But after all the things this group of unlikely friends went though to reach the surface they could not imagine life with out each other. It was a lively morning, Papyrus kept trying to keep Sans from eating the food before it was all done, Frisk and Flowey just giggled at the brothers, now playful banter. Life was truly peaceful and happy.

Thanks to Frisk's determination to be kind to everyone no matter what. With the help of the skeleton brothers plus Flowey, Frisk was able to save the underground. She melted the once cold hearts of many monsters in the underground befriending all of them. A long the way she melted Sans's heart the most after a year on the surface the once friends became lovers. And a year after that they were married/mated. Sans and Frisk combined monster and human traditions. Frisk wore a chocker with a heart space jewel bounded by Sans magic marking her as his mate. Sans wears a gold ring engraved with Frisk's name. It has been a year and a few months since they were married/mated and the group was enjoying a peaceful life.

The once powerful leader of the royal guard The Great and Terrible Papyrus was trying really hard to hide his grin as he feed the ducks with Sans. Of course Papyrus was feeding them the best bird seed they could find. Sans was resting up against a near by tree with one socket open, Papyrus lets him nap a bit more now, but he did not want to completely fall asleep seeing Papyrus smiling brought back happy memories of a time long forgotten. Across the lake Flowey was wrapped around Frisk's arm even after all these years he is still very protective of his best friend Frisk. She knows this makes him happy so she never stops him, expect when she spends time with Sans. Frisk buys two ice cream crepes. At first he wondered how this would be different from nice cream. But after he tried it Flowey enjoyed the human nice cream. The group of friends did could not hear the low static noise of their world being ripped apart. A bunch of malware viruses in the shape of black and white krakens come into this version of the Underfell universe.

Malkens were never apart of the Undertale multiverse but they were brought into the multiverse by negative energy from the creators world plus another Frisk's curiosity about the creator's world. They are heartless viruses that travel from Au to Au collecting data from each of the worlds killing everything that gets in the way. Causing many Au's to die out before their time. They just collect the data to make more of them just like a hive of bugs would.

The Malkens started coming out from a hole in the timeline eating everything they could trees, people, monsters even ripping the ground apart. Monsters tried to fight back with magic which worked for bit but just like another pest problem more kept coming. Frisk tried to help many people and monsters get away. Sans and Papyrus with high L.V.s were able to keep most of the Malkens at bay but Frisk and Flowey were too far away to help. Sure Sans could use magic to bring his mate closer but that risked the chance of Papyrus being over taken by the Malkens it was only with there combined powers that Sans and Papyrus were able to keep the pest away.

"Frisk we need to go." Flowey said on her arm protecting her as best as he could.

"But not everyone has made it to safety." Frisk said as she looked at two monster sisters hugging each other in a corner.

"We can't save everyone LET'S GO." Flowey begged Frisk.

"No." Frisk said as she ran with determination taking her to the monster sisters. Flowey knew there was no stopping her now when she was like this. He tried his best to help her fend off the Malkens even with a low L.V. Flowey's magic was more effective then Frisk's human attacks, she did have a low L.V. of one after all.

Once they reached the girls Flowey tried his best to protect them all as he made a path back to Sans and Papyrus. His HP was taking quite a hit but he would not let Frisk or the monsters he had to protect get hurt.

"SANS GO GET YOUR HUMAN MATE ALL READY! THESE THING ARE NOTHING FOR ME JUST GO save Frisk." Papyrus said as he used magic against the horde of Malkens.

"Sure thing Pap." Sans said as he was about to rush to Frisk's side. A larger Malken grabs Papyrus leg bring him down.

"HOW DARE YOU THING!!" Papyrus says he hits the Malken with a red bone. Another rushes at him attacking his Arm.

"Pap.." Sans says as he starts moving towards Papyrus.

"NO SANS GET FRISK...I AM..fine..tch." Papyrus yells.

Sans teleports near Frisk getting more of the Malkens.

"AHHHHHH." Papyrus yells in pain as another Malken attaches it's self to Papyurs's arm making him unable to attack.

"PAPYRUS!!!!" Sans screams as he tries to blast both the Malkens away from his brother and his mate.

"Sans just go Flowey and I got this." Frisk says.

"But Frisk..." Sans says "I will be back soon."

"I know you'll always be there for me, now go." Frisk says as Sans teleports back to Papyrus's side.

After Sans kills all the Malkens he see a horrible sight. Papyrus's right arm is gone and he only has very few HP left.

"BROTHER THIS is nothing...I could have.." Papyrus says as he tries to stand tall but he falls down into Sans arms.

"Bro I know you're powerful, but..." Sans says.

"But Frisk.." Papyrus said.

"She has determination remember." Sans says.

"SHE WOULD HAVE TO HAVE DERTERMINATION TO MATE SOMEONE AS SMELLY AS YOU. I am going to have to bathe for days when we get back, having to depend on you like this  
you shitface." Papyus says. But with a small smile

"Anything for my asshole brother." Sans says as he smiles too.

Frisk and Flowey along with the monster sisters were running closer to Sans and Papyrus but the ground under them started to split. And the half that Frisk and company where on started to fall backward into a dark black pit. Flowey tried his best to hold on to everyone but he was losing his grip. Sans ran towards the break in the ground, holding Papyrus all the way, he was using a lot of his magic just to keep him and his brother from falling to the other side. On their side there was no black pit but they did not want to be far from Frisk and Flowey.

Flowey groaned in pain as he tried to keep everyone safe.

"Flowey throw the youngest sister first and Sans catch her with your magic, we have to do this one at a time." Frisk said.

Sans and Flowey both nodded and did what Frisk told them to and it went great the younger one was safe. But the tree Flowey was holding on started to break and they all fell further away from Sans.

"Flowey you can't hold us both, just swing over to Sans with her I will be fine." Frisk begged.

Flowey did not want to leave his best friend but the look she gave him, he just had to listen to her request. Flowey wrapped himself around the older sister and got closer to Sans. With Sans magic he saved them both.

"Now Frisk we don't....NO NO NO." Sans started to say. A Malken started moving closer to Frisk eating away at her tree he tried using magic to attack it but the more he used to save her the less magic he could use to hold everyone up. The younger sister started slipping, Papyrus tried to hold her but then he started slipping. Sans was really stuck in a hard place either save his mate or let his brother, Flowey and the monster kids fall. At first it was an easy choice Frisk cared more for him then anyone ever did and only recently has Papyrus been nice to him all those years of fighting and heartache can't just go away after a few nice words. So he used more magic to save her, Papyrus, Flowey and the monster kids started to fall Sans could only hear their screams a bit. He was happy with his choice until he locked eyes with his mate that he was fighting so hard to save. The look Frisk gave made him feel so guilty so he went back to holding the other group. Frisk smiled as she tried to climb closer but she lost her grip and fell into the black pit all she could hear was Sans screaming her name. Then everything went black and she fell for a long time.

A tall skeleton with a lazy grin a lollipop stuck in his mouth, an orange shirt on top a black hoodie. With dark green shorts and orange croc shoes. Not the most fashionable of skeletons but he never cared for that everyone loved him anyway. He was enjoying a fun time at Muffet's making jokes and everyone was laughing. But he heard a weird static noise that he never heard before so he wanted to just it check it out after all things have been so boring.

"Papyrus.." Muffet said.

"Just put it on my tap you know I am good for it." Papyrus winked a few girls in the dinner blushed. Papyrus may only pay a bit of his very high tap, but he does bring in lots of customers and that means extra G and Muffet loves G so it works out.

Papyrus kept teleports closer to the new sound. A bunch of broken trees were scattered across the forest. Neat he wondered what could have caused this, in the middle of the debris was a human girl knocked out cold. She had short brown hair a red and black sweater with stripes. And a black skirt and leggings with brown boots. Nice it has been so long since a human came down, but normally they come through the ruins. He wont have to keep that promise to the old man since he never meet this human. Papyrus smirked at that thought this is going to be fun if you play nice human. With his feet Papyrus lightly tapped the knocked out Frisk.

Frisk rubbed her eyes and she started to get up it was so cold why. She looked around and was shocked it looked just like Snowin forest except it was not as dark as before and with more broken trees. And in front of her was a different skeleton who looked a bit like Papyrus but with not so many scars or pointed cheekbones.

"Hey, what's up?" Papyrus said

"umm.." Frisk said as she looked up.

"Wow what a weird black hole." Papyrus said as he looked up at the hole Frisk fell from. "Well now it's gone..hehe neat." Papyrus said as the hole closed.

"My name is Papyrus by the way, Papyrus the Skeleton." Papyrus said as he offered Frisk his hand.

There is no way he could have the same name as her dear friend there is no way, unless Papyrus is a common name like Chris or something. But still where is this place and why does it look like Snowin. Is there a way for her to get back to Sans. Many things where running though Frisk head as she grabbed the hand of this new skeleton.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
[This is a picture of the Malkens](https://lightrina.tumblr.com/post/159181299093/a-malken-from-the-new-fan-fiction-i-am-writing)

 


	2. New friends

**Summary for the Chapter:**

> Papyus and Frisk get to know each other a bit more, plus she meet underswap Sans for the first time.

Frisk grabbed Papyrus's hand as he pulled her up from the ground. To her this Papyrus looked a bit like her best friend The Great and Terrible Papyrus. But he had a lazy grin, and he seemed really laid back nothing like the angry skeletons she has grown to love. Sans would be upset at her for being so trustworthy but that's just how she is.

Papyrus could not believe how soft the humans hands were, her cheekbones were in just the right shape. As he picked her up Papyrus could feel her ulna under her soft skin they too were a nice shape. Papyrus looked down on Frisk from what he could see lining the edge of her shirt was her lilac crest damn he thought she has a really nice crest. Frisk was  
looking up at him waiting for him to say something as she looked around.

"So...you're a real human huh?" Papyrus said.

"Yes, I am but I thought all monsters left the underground." Frisk replied.

"No we have been trapped here for years, The Queen wants all human's souls to break the barrier she is only missing one." Papyrus said.

"You said "Queen" right, I thought King Asgore was in charge plus my mom would never want to use the human souls to break the barrier sure she is strict but she never wanted to give the souls to Asgore." Frisk said.

"Asgore is not a king anymore he left his post many years ago and no one knows where he has gone since..." Papyrus said deep in thought.

Papyrus used to study anomalies under that hooded figure many years ago. Could Frisk be one could she actually be a human from a different timeline or even an alternate universe where Asgore is King and monsters are free.

"Tell me more, what do you know about the underground?" Papyrus asked.

Frisk told him everything about her world, how it was a kill or be killed world, how she with the help of her friends was able to save everyone there with kindness and trust.

"heh...what a weird world, it just seems too hard to believe but I did see that weird black hole you must have fall down from...since I am such a nice guy I will let you stay with my brother and I. In till we can find a way to get you back, I used to study that kind of stuff you know maybe I can find something. After all I can't just leave such a cute girl to be on her own." Papyrus said.

With all the things she said Papyrus believed she really came from an alternate universe or different timeline, everything was so different from the world he knew but she knew almost everyone in the underground even if what she said was different from what they normally were like. It was really hard to imagine Alphys as a mad scientist, Undyne maybe she did have the brains for that. The thought of someone as strong as Aphys being in a lab coat and making robots fight for her almost made him giggle. Plus since Papyrus knew everyone there was no way a human could walk around the underground meet everyone and mix up their personalities just to make him believe they came from another world, without him knowing.

"Oh thank you but can't we just go threw the barrier?" Frisk asked.

"I think you came from another universe or time line, this underground is very different from what you told me. There is no way someone could mix up all those facts about people I know and seem to know them so will, even if I never seen you before." Papyrus said.

Frisk remembered all the resets she caused in her world so timeline change was something she was not new to. Still how would this skeleton know about timelines, Sans knew so maybe some skeletons knew about resets. Frisk hoped she didn't reset the timeline again, she was finally happy with how things turned out and she only reset after she kept on dyeing to save everyone. And Frisk didn't remember the reset button come up before she woke up from the fall.

"Come on I better let you meet my brother since you will be staying with us for awhile." Papyrus said as he walked threw Sans's gate.

Frisk fallowed Papyrus threw the gate and more deeper into the forest. They pasted a wide open gate. It was nothing like the gate Frisk knew, the one she remembered had spikes around it and was a bit harder to fit threw. They walked over to the place that should have been her Sans's sentry station but instead of old mustard packets on the ground there was lollipop wrappers. A loud Mweh heh heh come out from just ahead of them. Frisk looked at where the sound came from and saw a smaller round skeleton with gray battle armor, black pants and matching blue gloves, scarf and boots. This new skeleton had a round face like Sans but no sharp teeth but instead a big grin with straight teeth. This new skeleton had bight blue eyes.

"PAPYUS WHAT WERE YOU DOING? I came looking for you and you are not at your post." the new skeleton said.

"Sorry bro, I just had to help someone out." Papyrus said.

"Though I do admire that fact that you helped someone, for that is something I, The Magnificent Sans am the greatest at." Sans said.

Now Frisk was really confused are all skeletons named either Sans or Papyrus. Or could this place be another universe like her's just different, the same people she knew and loved just things swapped around from what she knew.

"You really are the greatest at it bro." Papyrus said.

"I Am The best helper the underground has ever known." Sans said.

"So being the greatest helper ever you would help anyone right?" Papyrus said.

"Yes I will help anyone good, evil, tall and short I the Magnificent Sans am a friend to all." Sans said proudly, scarf flapping in the "wind".

"Even if that person in need was a human?" Papyrus asked.

"Oh course it doesn't matter that they are a human, I help everyone." Sans said as he stood proudly.

Papyrus looked over at Frisk and mouth out the words wait for it. Then he looked back at Sans.

"...Wait did you say human?" Sans asked.

"Yep." Papyrus said.

"HUMAN, HUMAN HUMAN!!!!!" Sans yelled happily as he jumped around then he ran a gave Frisk a big hug.

"Fear not human for I the Magnificent Sans shall help you in what ever you need, but do you think you could try out my puzzles you know so they can be ready for the next human." Sans said as he looked up at Frisk.

"Sure I like puzzles." Frisk said as she thought about her Papyrus "death trap" puzzles he made her do. She may have died one or twice doing them but it was worth it to become his friend plus solving his puzzle was like going up against an old cartoon villain evil laugh included. She could not help but smile she will do what ever it took to get back home to them.

"You like puzzles wowee you must become my friend." Sans said.

"Sure." Frisk said as she smiled

Hand in hand the smaller Sans waked with his new friend back to Snowdin. Along the way Frisk talked to Sans about how she needed to get back home to her family and that Papyrus would help her.

"You can stay as long as you need Human Frisk, though I do hope my brother helps you." Sans said.

"He can be a bit of a lazy bones." Sans whispered

Papyrus just smiled and shrugged. What his brother said was true, but this human he could kill her when ever he wanted since it's not breaking his promise that he made to his friend. 'Don't kill the next human that walks through this door' And since Frisk fell from the black hole she did not walk through this door so if she is bad he can kill or good will Papyrus will just have to see. He is a good guy deep down that's why everyone loves and trust him. But it can get boring sometimes having this human around could be fun plus maybe with her help Papyrus could save the old head scientist.

When the group made it back to Snowdin town it was different from what Frisk knew. The town was lit up for the holidays Cat people walking around happily with each other, Asreil ran by Frisk with his striped coat that coved most of his body it made it look like he had no arms. Frisk looked at him a bit longer her Flowey was stuck as a flower but she knew he had once been like that too. The group made it to the skel bro's home, it was clean and bright inside no cracks in the wall. Sans made them tacos for dinner it was pretty good. Then Sans went to bed after Papyrus read him a story. Frisk just sat on the couch watching the TV it was hard to believe that Napstablook was a robot and his music was so good. Her Napstablook liked edger music and made fun of Metteton all most everyday but that just made him want to be a star more. Everything was fine between them now after Frisk set everyone free. She was almost falling asleep.

"Hey...Frisk." Papyrus said.

Frisk looked up at him, Papyrus was upstairs.

"You can sleep in my room, being my guest and all." Papyrus said as he pointed to his room.

Frisk walked up the stairs and went into Papyrus's room. He smiled at her as she passed by saying goodnight as he walked downstairs. Papyrus's room was very much like her Sans's room, messy, things flying, and an un made bed. Just no mustard smell, Frisk could not believe she actually missed that mustard smell. She loved her Sans to death but some times she would steal his coat and shirt just to wash it. Sans...she wondered how he was doing if he could even sleep, he had such a hard time sleeping before they got together. Frisk hugged a pillow as she fell asleep her heart aching for the family and life she missed.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
[Here is a picture of Frisk from Underfell](https://lightrina.tumblr.com/post/159556901333/my-head-cannon-for-underfell-frisk-plus-this-is)

 

**Notes for the Chapter:**

> I have a Tumblr https://lightrina.tumblr.com/


	3. Ch 3 I want you

**Summary for the Chapter:**

> Papyrus and Frisk try using the machine but it fails, Papyrus tries to cheer her up but all that does is makes him fall more in love with her.

**Notes for the Chapter:**

> There will be some Smut in this Chapter, plus it is from Papyrus's point of view
> 
> Come fallow me on Tumblr I post drawing sometime https://lightrina.tumblr.com/s

It has only been a week or so but Frisk seems to like Snodin so far it took her a while though. At first she seemed a bit weary of the other monster, beside me and bro. But after hanging around with us doing puzzles and chilling at Muffet's She began to see monsters here aren't so bad. Even with their violent tendencies Frisk seems to still care a lot about her monsters from her world when we talk about it.

One night when Sans was staying over at Alphys's, we had a movie night Frisk picked the movie it was about people fighting to survive and growing up in a hard world.

"My underground is a lot like that or was like that until I freed everyone." Frisk said resting on the couch.

" A kill or be killed world huh...how could someone so kind as you even survive a world like that?" I asked her.

"You should always be kind and forgive. My Papyrus killed me four times with his traps and my Sans maybe three before I won them over making them my best friends." Frisk said smiling.

"Why would you put that I would have said fuck it. " I said.

"Flowey was with me the whole time at first he only wanted to save me and get me out of the underground, but after traveling with him I wanted to save everyone since I had the power of resets I thought I should put it to good use." Frisk said.

Who knew anomalies could use their power for good Temmie sure did not use his power that way, not like I care anymore but still, had Temmie used his power like Frisk maybe we could be free too.

"Can you reset now in my world?" I asked.

"I tried yesterday but it won't let me I see the button but no matter how many times I try it wont work like before." Frisk said.

"That's lame but for the time being you can stay in my world as long as you like, I only ask that you stay in Snodin, my Alphys is a human hunting master she killed the last two humans on her own. I don't know if I could protect you from her, plus I wouldn't want my bro to be torn between his two best friends. You being here has really made him happy human Frisk. He didn't have much friends before you." I said

"You two have all ready done so much for me I could never do something that would cause you trouble. I don't mind staying in Snodin it's easier to stay here so we can work together to get me back home." Frisk said.

We went back to watching the movie, true I am helping her with my science notes and knowledge of timelines and anomalies. But I only worked with Dr. River for so long, no one even remembers them. We managed to make a little portal but it only stayed open for a bit. At least it kept Frisk hopeful that I can help her go back. But the more I hear about her world the more I DON'T want her to go back. Sure they have the surface now, but they kill each other so easily. How could anyone hurt someone like Frisk. With her smooth vertebabe...I thought as I looked over at her exposed skin. We played a few more scary and horror movies after that Frisk really likes this stuff. Soon she fell asleep at first she just rested on her side but after a few minutes she rested on me. It felt...nice...I sighed I was glad I didn't fall asleep first like normal. She looked even cuter like this as I stroked her hair. She must have liked it too because she hummed and started to cuddle me. It felt so good with her soft flesh rubbing against my cold bones I started to purr. I really liked were this was going...I care about Frisk I want her to be safe and happy like this moment. But it did not last for long.

"Sans...I...I need you...don't go." Frisk said in her sleep as she gripped me tighter.

I know for a fact that there is no way she is taking about my Sans. Sure they are friends but I never seen her get this close to him. I got up from the couch, no mater how good that felt I didn't want her touching me while thinking about her Sans. Frisk woke up soon after I got up.

"Sorry did I fall asleep." Frisk said as she rubbed her eyes.

"Yeah but it's late anyway do you want to stay here or sleep back up stairs?" I asked.

"I could stay here you must need you bed, since I been borrowing it all this week." Frisk said.

"It's fine really you're my guest." I said, MY Human I thought.

"No just for tonight." Frisk said as she pulled the blanket around her.

"Ok, ok if you insist, you really are a kind human Frisk." I said as I walked up stairs.

Stars she really is so sweet, my human Frisk, I do care about her a lot. I closed my door before I lie down on my bed, man it smells so good just like her. My soul started glowing remembering how it felt to be near her. I been with a few monsters before so lust is something that is not new to me, but it never felt like this before just touching her lightly and having her scent near me is driving me crazy it feels so good. But I have to help her I...promised her after all. I will try to put my feelings aside for her sake, my sweet human Frisk.

___________________________________________________________________________________________________________________________________________________

Another week went by and with her help and my old machine we were able to open the portal a bit more but all the worlds we could see were not Frisk's. The last world we saw had Sans in a blue hoodie sleeping at his station. We were going to try and open another one but my machine started having problems, it over heated and the portal glitch out.

I tried to fix it as best as I could but everything I tried only made the machine black out again and again. I looked over at Frisk she looked sad I hated seeing her like this.

"Hey how about we get something to eat...Napstablook hotel it has really fancy food, I hardly go myself I think I can treat ya this time." I said as I gave her a wink.

"But isn't that near Alphys's place? " Frisk said.

Darn I forgot but still I wanted to cheer her up so badly, I teleported back to my room and grabbed an extra hoodie of mine. Then I handed it over to Frisk.

"Wear this with the hood up my scent should mask yours to most monsters they will think you're one of them." I said.

After she put on the hoodie I grabbed her, man do I love the feeling of her flesh.

"I know a short cut...but you need to be close." I said as I teleported her to Napstablook hotel.

I still love the taste of my honey lollypops better then anything else and Muffet's honey based treats I love them too but this food was not to bad. Frisk seemed to really like it she started smiling again. This place is a very date like place but I hope she doesn't mind too much. We talked a lot about timelines and resets she was just so smart. I had a great time, I never had so much fun eating with anyone ,that I ever took on a date before. To Frisk I guess this was not a date. I had to pay the bill and the line was kind of long so Frisk waited for me near the fountain. I thought I was not gone too long but I must have because when I came back Frisk was surrounded by a few monsters and they were hitting on her. How DARE they even come near her. I ran toward her and quickly teleported her back home, but after that I teleported right back. I grabbed a few of them a pushed them into an ally away from view. I beat them up pretty good, I only let them go when they said they would never come to Snodin or Frisk again.

"Why is this chick so important Papyrus when I normally picked up your chicks with you never cared before. I though you were done with her since she was alone and all." One said.

"I WAS only gone for a moment...but still leave this one alone SHE IS MINE. GOT THAT." I said as I threw him against the wall.

"Wow who knew Papyrus would ever find a mate he was such a playboy before." The other said as they carried their friend away.

"We better stay away we don't want him mad." One said as they fled.

Sure my world is not a kill or be killed one, but we are monsters and we have battles like any other world. And no one messes around with another monster's mate, we like to claim what is ours. Frisk I thought I could just be her friend. But the more I spend time with her the more I want her, NEED her. MY world is safer anyway she could just stay here, maybe I wont fix the machine, I will tell her it can't be fixed. I gave up finding Dr. River I could easily give up on finding a way to send her home, since she is home after all.

_________________________________________________________________________________________________________________________________________________________________

Two weeks went by and I did tell her that I cant fix the machine anymore. Frisk didn't take it very well she hardly comes out of my room any more. She drank all my mustard and she holds the bottle in her sleep. Frisk orders Togo from Grillby's sometimes and his little minions brings her hotdogs with fries and extra mustard. I had no idea she liked mustard so much. Sans seems to be worried about her too.

"Brother I am going to give Frisk the best cheering that only I The Magnificent can do but since that will take up much of my time, you need to do the laundry for once." Sans said as he pointed at me.

"I will bring her my best tacos, plus I will read her Fluffy kitty and my amazing hugs that will surly cheer up my dear friend. So you better help too lazy bones and do the laundry for me this time." Sans said as he carried his tray of tacos and favorite book.

"Sure thing bro...for Frisk, I am sure with your help we can have her smiling again." I said as I picked up the load of laundry and walked over to the laundry room.

"Wow Frisk is a good influence on my brother." Sans said as he walked up the stairs.

Normally I don't do laundry it's just too much work sorting out everything plus my stuff stinks a bit, when was the last time I washed this sock, I thought as I put up my stuff. I try to help Sans sometimes it's just every time I wash I fall asleep in the middle of the job its just so boring, the same thing over and over again. Just like timeline after timeline thanks to Temmie, my whole life became boring I used to love science, finding out new things, but after Dr. River went missing, life just became predictable. I even started messing with monsters making them believe I am this fun loving guy who really loves candy, I do love honey lollypops, their blind love and trust in me makes it less boring. But Frisk this human anomaly she is so sweet, smart and exciting. I want her so bad I bet she fells amazing just like when she rubbed against my bones. My soul just glows thinking about it all the fun stuff we could do together. My darling Frisk what I would not do to you. I licked my teeth just thinking about her lips pressed against my teeth, how after kissing for a bit I would enter my tongue passed her lips are tongue would move around each other she would let out a few gasps and morn at my touch. She would look at me with a lustful look begging for more MY Darling Frisk. I looked down at the laundry it started to smell sweat rather then mushy bones, this is Frisk's clothes, we brought her some new ones after she stayed with us awhile. In my hand I held Frisk's old panties her scent was amazing I brought it close to my face and smelled so much of her sweet scent. My soul glowed so much wanting her, NEEDING her. My magic glowed most in my pelvic area, my other hand went down my shorts to where my dick appeared. I sniffed her panties as I stroked my dick thinking about what it would fell like to come inside MY Frisk. I would push her down on my bed not caring about fixing it up. After kissing her sweet skin I would slowly remove all her clothes maybe even taking her panties off with my teeth. Then she would lie there looking up at me wanting more. I can't leave the poor girl helpless can I so I would thrust my dick deep inside her womanhood. Our souls would beat as one as I plow in her, Frisk's hands would be moving up and down my rib cage as I bring her close to ecstasy. I would pick up my speed as her screams got louder in till we climax together, I would put all my seed in her not wasting anything she deserves it all. I look down at my hand seeing that there is a little extra mess on the floor now, I wiped it up with the other dirty clothes, it will get clean in the wash plus Sans would be so mad if I left it there. That was one of the best times I had jacking off in a long time, oh Darling Frisk you will have such a wonderful time in my world, you will NEVER go back, your mine now Frisk, I WILL make you mine if I have to.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[Here is a Picture of this Story's Underswap Papyrus](https://lightrina.tumblr.com/post/160597345558/my-yandere-papyrus-from-you-can-stay-in-my)

 

 


	4. Chapter 4

**Summary for the Chapter:**

> Underfell Sans will try anything to bring his mate back even if that means getting along with these multiverse travelers.

~~~~~~~~~~~~~~~~~~~Meanwhile back in Underfell~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
"FRISK!!!!!!"  Sans yelled as he watched the one he loved fall into a deep hole.

Even if Papyrus and Flowey were both yelling at him to stop, Sans kept running. If she was going to be lost to time like Gaster, no matter how much of a jerk he was, Sans could not lose anyone else. He kept running toward the portal that Frisk fell through just when he was about to reach it the portal closed on him. The world around him was broken but no portal was to be found. Sans stood there for a bit before his eyes went dark as he fell to the floor. No no, it can't be not again not Frisk Sans thought as he laid on the ground. The monster sisters ran away with other people, but Papyrus and Flowey went to Sans side. Papyrus even if he only had one arm now, was trying to shake his brother out of this. Even hitting him a few times yelling him to snap out of it, Flowey was begging them to run away so they could be safe and to not let Frisk's sacrifice be in vain. But Sans eyes were very dark and his face had the same blank expression he could not hear them at all his soul could not take the loss of his love.

"I got this one closed Jay, how are things on your end?"

"I think I got most of them, man I wish we got here sooner, A lot of people died."  
Papyrus looked over to see where the voices were coming from, the first voice came from a rather tall cat monster with black claws, a leather vest and a striped shirt with ripped pants.  The other one was a skeleton, taller then Sans but shorter then Papyrus. He looked a lot like someone Papyrus used to know but he can't remember who and a bit like Sans. Jay had green eyes and wore lots of leather too.

"Paws you done with all the portals in this universe?" Jay said as he walked closer to Paws

"Yep all of them are closed Malkens won't be getting out anytime soon." Paws said as he looked at his tablet.

"Now we just have to wait for Chi to kill the mother." Jay said then he saw Sans and Papyrus "Oh it's them we better move." Jay said as he tried to push Paws away.

"Why we already told Chi to meet us here." Paws said as he stood still.

"You...know...how...she gets around Sanses and Papyruses...I just want to get this done then go home." Jay said as he tried to push Paws away.

"What is so wrong with being a Papyrus plus how do you know my name and my brother?" Papyrus asked.

"AHHHH I don't have time for this we just have to go now," Jay said pushing even harder.

"Don't have time for what Jay?"

Papyrus looked over to where the voice was coming from and his jaw dropped it could not be...Frisk? Sure this human female looked like Frisk but just a few years older plus her hair was short like Frisk's but one long braid in the back. She wore lots of leather too with shorts and stipped sleeves. This Frisk was also carrying a sword that had a gaster blaster on the handle. It went away as she walked closer to Jay.

"I killed the mother we can go, but what are you trying to hide from me, Jay?" Chi said as she looked behind him. "Oh...the Sans and Papyrus of this universe. At least this one is small like mine was." Chi said with a smile.

Sans finally opened lit his eyes and he saw Chi and ran to her.

"Frisk is that you? You look a bit different but I know my sweetheart anywhere...Frisk babe why aren't you hugging me." Sans said.

"I was a Frisk a long time ago now I call myself Chi. My story is long and sad, but long story short I lost my world, fell in a portal, got saved, went on a long journey to try and find my whole in the multiverse only to find that I could not save it. Now here I am saving other universes from Malkens and so they don't have the same fate." Chi Said.

"Multiverse, what Gaster was studying could it be true?" Sans said.

"Yes and you have no idea how big it really is, you could spend a lifetime looking, I know I did," Chi said sadly.

"WE ARE Going now, the mission is done. " Jay said as grabbed Chi's arm then glared at Sans.

"Wait please don't go, my Frisk fell into one of those portals you have to help me find her," Sans begged.

"Look we help the multiverse we don't have time to save every Frisk, its just tough luck dude," Jay said as he walked away.

"She is my everything I never had hope in till I meet her please I love her with all my soul,"  Sans begged he normally would not do something like this but these people knew more about the multiverse then he ever could, and he was not about to let the one chance of getting Frisk back walk away.

"Do you really love her?" Chi said as she looked back at him.

"CHI nooo,"  Jay said.

"Chi Yes," Chi said as she walked back toward Sans.

"Prove it, let me look at you and your soul, I meet lots of Sans many say they love Frisk but it was really nothing but an obsession or passing feeling. If you really love her I will help you, if you don't then there is nothing I will do." Chi said as she kneeled near Sans.  
Sans nodded his head, he was willing to do whatever it took to get back his Frisk. Sans summoned his soul and slowly handed it over to this human. Chi held the soul in her hands and could fell the love and devotion that this Sans had for his Frisk. She could fill the connection that these two had, in time Chi could find where this Frisk was at and hopefully save her.

"I think I can find her but you must come with us, back to the lab so I can use your connection to her to find her," Chi said. Before she let go of Sans soul.

Sans looked up at this older Frisk or Chi he could have sworn he saw a tear go down her face.  
Chi opened a portal and everyone went through, Jay was not happy with the new company but he also didn't want to make Chi mad. Paws showed Papyrus and Flowey to there new rooms. Sans fallowed Chi and Jay to the lab. Sans looked around and it did not seem too different from the lab Gaster used to work in before the accident.  They pasted many doors one door they pasted made Sans stop for a bit, he could not believe it there was an Alphys and a Undye in a lab coat. Something his Undye would never do, but what really shocked him was the man standing next to them...Gaster, it could not be. Gaster looked over at Sans a bit then gave a quick smirk before returning to his work. Sans was about to go in and ask him something but he felt a hand pull him back.

"He is not who you think he is, this world is a mix up of monsters who lost their world and had nowhere to go This Gaster started this lab to help monsters in the multiverse from world killing things like Malkens," Jay said. Then he started following Chi again.

"The sooner she helps you, the sooner you can leave," Jay said.

Sans went after the taller skeleton, soon they reached the room Chi wanted to go to. Chi started up a computer and was busy looking up things on the computer. Jay looked over at Sans and rolled his eyes.

"You can't save every Sans you know," Jay said.

Chi was quit she just looked back at Jay with a poker face then returned to her work.

"tch...fine but I won't help you this time darling," Jay said.

"Fine," Chi said as she kept typing away, without even looking at him as he walked out the door.

"You two seem to get along swimmingly." Sans said as he sat down.

"He means will, our relationship is hard, complex but we stuck together by this universe's law, were 'soul mates' we stuck together if one dies so does the other. We fell each other's life force etc. Its this life force connection I have been studying here, when I felt your love for Frisk I knew I could use that connection to search the multiverse to find her and save her. Your connection is still storge so I am positive she is alive somewhere out there." Chi said.

"The life force connects you to your mate," Sans said.

"Ech...he's not my mate...will not in the way you are to Frisk, but yes this connection binds us together, no matter where I am in the multiverse Jay can find me and whatever he is felling I can too, it helps with work when we have to split up we can always find each other. Jay is a good partner but I never really wanted him as my mate." Chi said looking down.

"I mean he is not as handsome as me but he is a good looking guy," Sans said. Not too sure why he was defending this Jay fellow but he could tell by the way Jay looked at Chi when she was not looking that he did care about her.

"You are handsome," Chi said smiling.

"HEY, I am a happy mated guy we are trying to find My Frisk remember, MY mate," Sans said blushing a bit, Chi did remind him of Frisk after all.

"hehe sorry I couldn't help it...but you kind of look like him, an edgy version of him, but still you remind me of him," Chi said.  
"Remind you of who?" Sans asked.

"My Sans...the one I lost along with my world. You would think after looking through the multiverse for years, seeing every version of him imaginable and even finding my dead world. That I could move on from the loss of my mate." Chi said.

"Your mate then why could you not use your connection to find him on this computer you have?" Sans asked.

"The connection my soul has with Jay is stronger even if I don't like him as my 'mate' plus I built this computer,with help from Gaster, Aphys, and Undye, to study 'soulmates' and 'mates' the connection they share and how no matter how far they are apart they will find each other again. But it only works when both parties are alive so it does not work for me and my lost mate." Chi said.

"How do you know your mate is gone do you not fill him anymore?" Sans asked.

"My soul still has his mark...but my world was nothing but dust and messed up data not a soul to be found. I tried to use the computer to find him but all it did was lead me to other Sanes plus Jay's connection messes up with the data. Jay, on the other hand, I can find him with or without the computer *sigh* so I know it works for other mates too. Jay says the mark only has not gone away is because of my "Human emotions" that I need to expect that My Sans is gone along with the world. But a part of me still believes that its still there because he is out there somewhere, silly huh?" Chi said.

"I don't think so. You must have really loved him that's why you were sad when you found out how much I love my Frisk." Sans said.

"Yes and that's why I want to help you both, I may not be able to be with my Sans but at least I can help another Frisk have her happiness. Now let me see your soul again I need to connect it to the computer." Chi said as she hooked Sans up.

"I know its personal but think about your Frisk and your love for her so your connection can grow stronger, making it easier for the system to find her," Chi said as she looked at the computer.

Sans did as he was told sure he didn't like playing 'nice' with this 'Frisk' or Chi as she likes to be called but if there is any chance of finding his love, mate Sans would do anything even swallow his pride for a bit. After thinking about his mate as he looked up at the screen many Frisks passed buy the screen, he saw young ones, older ones like his, Frisks in different outfits that were not black and red. Some Frisk even had a cold look in their eye, but none was his.

"Were getting closer...she must be in this pocket somewhere..." Chi said as she looked on the computer.  
But soon error buzzes started to come from the computer. And Sans felt like he lost Frisk their connection was broken, he felt like she was ripped from existence just like him no no Sans thought. After that he felt her again could it be a reset he hoped for once.

"She died and reset in another world, that must be why we lost the connection, it must be we have to try again," Chi said as she typed away

Sans did try again, but the error came back again and again. Sans felt his love die again and again someone or something is killing his Frisk, again and again, making it harder to find her, no matter how much it hurt he kept on trying this connection is the only chance he has of finding her. Soon after a few tries, the computer blew up.

"No no this never happened before," Chi said as he tried to fix the computer, only to be pulled away by Jay who shielded her from the bast.

"I thought you said you wouldn't help," Chi said half smiling.

Jay rolled his eyes but still smiled back "You jerk" and then he boopped her head.

Gaster, Alphys, and Undye from this world came running in. Gaster asks what happened after Chi told him both Alphys and Undye were studying the remble.

"Because she kept resetting the connection got lost and with how big the multiverse is the computer could not handle restarting each time," Undye said.

"A computer likes this needs lots of power to search the multiverse, after all, it took all three of us to make it with the help of Chi and Jay," Alphys said.

"It's going to take a long time to rebuild, do you want to stay Sans?" Gaster turned to Sans as he spoke.

"No matter how long it takes I will stay, this is the only hope I have to get her back. Plus I know a bit about science too maybe four heads will be better than three." Sans said.

But in his soul he could still fell her dying and coming back to life, whoever is doing this has no idea who they are messing with they will pay for everything that happened to his Frisk.

 

[Picture of Paws](https://lightrina.tumblr.com/post/168743636763/this-is-paws-he-is-a-character-in-an-au-i-am)

**Notes for the Chapter:**

> Paws, Chi and Jay are from new AU I am making too.


End file.
